This invention relates to a planetary speed change gearing built in a flywheel interposed between a power transmission shaft of an engine and an output shaft connecting the engine to a machine to be driven.
Heretofore, when a generator, a pump or other machine to be driven is directly connected to a rotary power transmission shaft of each of various types of prime movers, it has been necessary to mount a speed change gearing in a power transmission system if it is required to change the rate of rotation of the prime mover before rotation is transmitted to the driven machine.
However, mounting of a speed change gearing between the power transmission shaft of the engine and the output shaft for directly connecting the engine to the driven machine has the disadvantages that the power transmission system including the speed change gearing becomes large in size, heavy in weight and high in production cost.